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105KE Basin Area Radiation Monitor System (ARMS) Acceptance Test Procedure

Description: This procedure is intended for the Area Radiation Monitoring System, ARMS, that is replacing the existing Programmable Input-Output Processing System, PIOPS, radiation monitoring system in the 105KE basin. The new system will be referred to as the 105KE ARMS, 105KE Area Radiation Monitoring System. This ATP will ensure calibration integrity of the 105KE radiation detector loops. Also, this ATP will test and document the display, printing, alarm output, alarm acknowledgement, upscale check, and security functions. This ATP test is to be performed after completion of the 105KE ARMS installation. The alarm outputs of the 105KE ARMS will be connected to the basin detector alarms, basin annunciator system, and security Alarm Monitoring System, AMS, located in the 200 area Central Alarm Station (CAS).
Date: December 14, 1999
Creator: Kinkel, C. C.

2000 Census: Contingency Planning Needed to Address Risks That Pose a Threat to a Successful Census

Description: A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the Year 2000 census, focusing on: (1) the need to boost the declining level of public participation in the census; and (2) the Census Bureau's need to collect timely and accurate data from nonrespondents."
Date: December 14, 1999
Creator: United States. General Accounting Office.

3D visualization of port simulation.

Description: Affordable and realistic three dimensional visualization technology can be applied to large scale constructive simulations such as the port simulation model, PORTSIM. These visualization tools enhance the experienced planner's ability to form mental models of how seaport operations will unfold when the simulation model is implemented and executed. They also offer unique opportunities to train new planners not only in the use of the simulation model but on the layout and design of seaports. Simulation visualization capabilities are enhanced by borrowing from work on interface design, camera control, and data presentation. Using selective fidelity, the designers of these visualization systems can reduce their time and efforts by concentrating on those features which yield the most value for their simulation. Offering the user various observational tools allows the freedom to simply watch or engage in the simulation without getting lost. Identifying the underlying infrastructure or cargo items with labels can provide useful information at the risk of some visual clutter. The PortVis visualization expands the PORTSIM user base which can benefit from the results provided by this capability, especially in strategic planning, mission rehearsal, and training. Strategic planners will immediately reap the benefits of seeing the impact of increased throughput visually without keeping track of statistical data. Mission rehearsal and training users will have an effective training tool to supplement their operational training exercises which are limited in number because of their high costs. Having another effective training modality in this visualization system allows more training to take place and more personnel to gain an understanding of seaport operations. This simulation and visualization training can be accomplished at lower cost than would be possible for the operational training exercises alone. The application of PORTSIM and PortVis will lead to more efficient planning overall and ultimately increase port utilization and throughput, decreasing ...
Date: June 14, 1999
Creator: Horsthemke, W. H.; Macal, C. M. & Nevins, M. R.

50x50 GeV Muon Collider Beam Collimation

Description: A summary of different techniques and systems to scrape beam halo in a 50 x 50 GeV {mu}{sup +}{mu}{sup -} collider is presented. Such systems are installed in a special utility section with optics specifically designed to meet both the requirements of the scraping system and of injection. Results froma realistic Monte Carlo simulation (STRUCT-MARS) show that a system consisting of steel absorbers several meters in length suppresses halo-induced backgrounds in the collider detector by more than three orders of magnitude. The heat load in superconducting magnets near the scraper system can be reduced to tolerable levels by appropriate collimator design and location. This reduction applies to both injection and collider mode of operation. Also discussed is extraction of halo particles using electrostatic deflectors and bent crys-tals, although neither appears to be effective for a muon collider at this energy.
Date: April 14, 1999
Creator: Drozhdin, A. I.; Johnstone, C. J.; Mokhov, N. V.; Garen, A. A. & Biryukov, V. M.

Accounting Standards: Treatment of Asset-Backed Securities

Description: Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on whether the greater discretion allowed to banks as opposed to securities broker/dealers under accounting standards and practices may have resulted in less transparency in the value of asset-backed securities held by banks, focusing on: (1) mortgage-backed securities (MBS); (2) the accounting treatment applied to securities (including MBS) held by banks and broker/dealers; and (3) the accounting for securities holdings by the six largest bank holding companies and whether such holdings might have affected the transparency of financial statements."
Date: April 14, 1999
Creator: United States. General Accounting Office.

Additional Interface Corner Toughness Data for an Adhesively-Bonded Butt Joint

Description: Over a period of 15 months, five sets of adhesively-bonded butt joints were fabricated and tested. This previously unreported data is used to assess the variability of measured interface corner toughness values, K{sub ac}, as well as the dependence of K{sub ac} on surface preparation. A correlation between K{sub ac} and the size of the adhesive failure zone is also noted.
Date: April 14, 1999
Creator: Guess, T.R. & Reedy, E.D.

Adjustment of the (235)U Fission Spectrum

Description: The latest nuclear data are used to examine the sensitivity of the least squares adjustment of the {sup 235}U fission spectrum to the measured reaction rates, dosimetry cross sections, and prior spectrum covariance matrix. All of these parameters were found to be very important in the spectrum adjustment. The most significant deficiency in the nuclear data is the absence of a good prior covariance matrix. Covariance matrices generated from analytic models of the fission spectra have been used in the past. This analysis reveals some unusual features in the covariance matrix produced with this approach. Specific needs are identified for improved nuclear data to better determine the {sup 235}U spectrum. An improved {sup 235}U covariance matrix and adjusted spectrum are recommended for use in radiation transport sensitivity analyses.
Date: September 14, 1999
Creator: GRIFFIN,PATRICK J. & WILLIAMS,J.G.

Adults With Severe Disabilities: Federal and State Approaches for Personal Care and Other Services

Description: A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on community-based, long-term care for severely disabled adults, focusing on: (1) the number and characteristics of adults with severe disabilities; (2) the federal assistance available to such individuals; (3) Medicaid coverage of personal care and related services; and (4) how a sample of selected states have implemented Medicaid policies that allow consumers to select their own caregivers, an approach called consumer direction."
Date: May 14, 1999
Creator: United States. General Accounting Office.

Advanced steel reheat furnaces: Research and development. Final report

Description: The purpose of this report is to present the results of two phases of a three-phase project to develop and evaluate an Advanced Steel Reheat Furnace (SSRF) concept which incorporates two proven and commercialized technologies, oxy-fuel enriched air (OEA) combustion and gas reburning (GR). The combined technologies aim to improve furnace productivity with higher flame radiant heat transfer in the heating zones of a steel reheat furnace while controlling potentially higher NOx emissions from these zones. The project was conducted under a contract sponsored by the Department of Energy (DOE). Specifically, this report summarizes the results of a modeling study and an experimental study to define and evaluate the issues which affect the integration and performance of the combined technologies. Section 2.0 of the report describes the technical approach uses in the development and evaluation of the advanced steel reheat furnace. Section 3.0 presents results of the modeling study applied to a model steel furnace. Experimental validation of the modeling results obtained from EER`s Fuel Evaluation Facility (FEF) pilot-scale furnace discussed in Section 4.0. Section 5.0 provides an economic evaluation on the cost effectiveness of the advanced reheat furnace concept. Section 6.0 concludes the report with recommendations on the applicability of the combined technologies of steel reheat furnaces.
Date: January 14, 1999
Creator: Nguyen, Q.; Koppang, R.; Maly, P.; Moyeda, D. & Li, X.

Aging and phase stability of waste package outer barrier

Description: After aging for 16,000 hr at 593 C, P phase was found at Alloy 22 grain boundaries. At higher temperatures (as much as 760 C for the same aging time), both {mu} and P phase formed on grain boundaries and within the grains. Grain boundary carbides also form at 593 C and higher, but the amount of carbide is small compared to the p and P phases. A small amount of sigma phase forms in Alloy 22 after 16,000 hr at 704 and 760 C. LRO was seen after aging for 16,000 hr at 593 C and for 40,000 hr at 427 C, but ordering most likely begins at shorter times. More work must be done in phase identification. Samples aged at times less than 16,000 hr must be examined so that the phase evolution during aging can be determined. A procedure being developed for phase extraction and x-ray diffraction should make phase identification and quantification of the relative amounts of each phase easier. The times at which various stages of intermetallic precipitation occur in Alloy 22 base metal displayed an exponential (Arrhenius-type) temperature dependence. The activation energy was determined to be 290 kJ/mol. A more quantitative model based on precipitate volume fraction measurements that can be integrated over a variable temperature profile must be developed before a reasonable prediction of the phase stability of Alloy 22 base metal under repository conditions can be made. In addition, the effect of intermetallic and carbide precipitation on Alloy 22 properties must be determined. Precipitation kinetics in weld heat-affected zones, as well as in the base metal, must be studied because the thermal pulse given the HAZ during the welding process may alter nucleation of intermetallics and therefore the precipitation kinetics. Intermetallic and carbide precipitates form in Alloy 22 welds during the welding ...
Date: July 14, 1999
Creator: Summers, T & Turchi, P

Analysis of In-Situ Vibration Monitoring for End-Point Detection of CMP Planarization Processes

Description: This paper details the analysis of vibration monitoring for end-point control in oxide CMP processes. Two piezoelectric accelerometers were integrated onto the backside of a stainless steel polishing head of an IPEC 472 polisher. One sensor was placed perpendicular to the carrier plate (vertical) and the other parallel to the plate (horizontal). Wafers patterned with metal and coated with oxide material were polished at different speeds and pressures. Our results show that it is possible to sense a change in the vibration signal over time during planarization of oxide material on patterned wafers. The horizontal accelerometer showed more sensitivity to change in vibration amplitude compared to the vertical accelerometer for a given polish condition. At low carrier and platen rotation rates, the change in vibration signal over time at fixed frequencies decreased approximately ½ - 1 order of magnitude (over the 2 to 10 psi polish pressure ranges). At high rotation speeds, the vibration signal remained essentially constant indicating that other factors dominated the vibration signaL These results show that while it is possible to sense changes in acceleration during polishing, more robust hardware and signal processing algorithms are required to ensure its use over a wide range of process conditions.
Date: May 14, 1999
Creator: Hetherington, Dale L.; Lauffer, James P.; Shingledecker, David M.; Stein, David J. & Wyckoff, Edward E.

Analysis of Strategies to Improve Heliostat Tracking at Solar Two

Description: This paper investigates dhlerent strategies that can be used to improve the tracking accuracy of heliostats at Solar Two. The different strategies are analyzed using a geometrical error model to determine their performance over the course of a day. By using the performance of heliostats in representative locations of the field aad on representative days of the year, an estimate of the annual performance of each strategy is presented.
Date: January 14, 1999
Creator: Jones, S. A. & Stone, K. W.

Anisotropy in Hydrogenated Amorphous Silicon Films as Observed Using Polarized FTIR-ATR Spectroscopy

Description: We used polarized attenuated total reflection (ATR) measurements together with Fourier transform infrared (FTIR) spectroscopy to investigate the vibrational spectra of hydrogenated amorphous silicon (a-SiH{sub x}) films 0.5-1.0 microns in thickness. We deposited the films using hot-wire or plasma-enhanced chemical vapor deposition methods (HWCVD or PECVD, respectively) on crystalline silicon and cadmium telluride substrates. Our ATR technique gave a spectral range from 2100-400 cm{sup -1}, although the Si-H wagging mode absorption band at 640 cm{sup -1} was somewhat distorted in the a-SiHx/Si samples by impurity and lattice absorption in the silicon ATR substrates. We report the identification of a Si-O-C impurity band with maximum intensity at 1240-1230 cm{sup -1}. The assignment of this band to a Si-O-C vibration is supported by secondary-ion mass spectrometry (SIMS) measurements. Our polarized FTIR-ATR spectra of HWCVD and PECVD a-SiH{sub x} films on <111> Si ATR substrates show that the impurity dipoles ar e oriented strongly parallel to the film growth direction. The wagging mode absorbance band is more intense in the film plane. This trend is less pronounced for the Si-H stretching vibrations. These observations are consistent with some degree of anisotropy or medium-range order in the films. The anisotropy in the Si-H bands may be related to residual stress in the films. Our scanning electron microscopy (SEM) analyses of the samples offer additional evidence of bulk structural anisotropy in the a-SiH{sub x}/Si films. However, the Si-O-C impurity band was not observed in the polarized ATR-FTIR spectra of the a-SiH{sub x}/CdTe samples, thus indicating that the Si substrates influence formation of the impurity in the a-SiH{sub x}/Si films.
Date: May 14, 1999
Creator: Webb, J. D.; Gedvilas, L. M.; Crandall, R. S.; Iwaniczko, E.; Nelson, B. P.; Mahan, A. H. et al.

Anoxic Plume Attenuation in a Fluctuating Water Table System: Impact of 100-D Area In Situ Redox Manipulation on Downgradient Dissolved Oxygen Concentrations

Description: Anoxic Plume Attenuation in a Fluctuating Water Table System: Impact of 100-D Area In Situ Redox Manipulation on Downgradient Dissolved Oxygen Concentrations
Date: June 14, 1999
Creator: Williams, Mark D.; Vermeul, Vincent R.; Oostrom, Martinus; Evans, John C.; Fruchter, Jonathan S.; Istok, J. D. et al.

Architecture and Performance of the PEP-II Low-Level RF System

Description: Heavy beam loading in the PEP-II B Factory along with large ring circumferences places unique requirements upon the low-level rf (LLRF) system. RF feedback loops must reduce the impedance observed by the beam while ignoring the cavity transients caused by the ion clearing gap. Special attention must be placed on the cavity tuner loops to allow matching the ion clearing gap transients in the high energy ring and the low energy ring. A wideband fiber optic connection to the longitudinal feedback system allows a rf station to operate as a powerful ''sub-woofer'' to damp residual low order coupled bunch motion. This paper describes the design and performance of the VXI based, EPICS controlled, PEP-II low-level rf system(s). Baseband in-phase and quadrature (IQ) signal processing using both analog and modern digital techniques are used throughout the system. A family of digital down converters provide extremely accurate measurements of many rf signals throughout the system. Each system incorporates a built-in network analyzer and arbitrary rf function generator which interface with Matlab to provide a wide range of functions ranging from automated configuration of each feedback loop to cavity FM processing. EPICS based sequences make the entire system a turn-key operation requiring minimal operator intervention. In the event of a fault, fast history buffers throughout the system write selected rf signals to disk files which can be viewed later to help diagnose problems. Actual data from commissioning runs of PEP-II is presented.
Date: April 14, 1999
Creator: Corredoura, Paul L.

ASME code and ratcheting in piping components. Final technical report

Description: The main objective of this research is to develop an analysis program which can accurately simulate ratcheting in piping components subjected to seismic or other cyclic loads. Ratcheting is defined as the accumulation of deformation in structures and materials with cycles. This phenomenon has been demonstrated to cause failure to piping components (known as ratcheting-fatigue failure) and is yet to be understood clearly. The design and analysis methods in the ASME Boiler and Pressure Vessel Code for ratcheting of piping components are not well accepted by the practicing engineering community. This research project attempts to understand the ratcheting-fatigue failure mechanisms and improve analysis methods for ratcheting predictions. In the first step a state-of-the-art testing facility is developed for quasi-static cyclic and seismic testing of straight and elbow piping components. A systematic testing program to study ratcheting is developed. Some tests have already been performed an d the rest will be completed by summer'99. Significant progress has been made in the area of constitutive modeling. A number of sophisticated constitutive models have been evaluated in terms of their simulations for a broad class of ratcheting responses. From the knowledge gained from this evaluation study two improved models are developed. These models are demonstrated to have promise in simulating ratcheting responses in piping components. Hence, implementation of these improved models in widely used finite element programs, ANSYS and/or ABAQUS, is in progress. Upon achieving improved finite element programs for simulation of ratcheting, the ASME Code provisions for ratcheting of piping components will be reviewed and more rational methods will be suggested. Also, simplified analysis methods will be developed for operability studies of piping components and systems. Some of the future works will be performed under the auspices of the Center for Nuclear Power Plant Structures, Equipment and Piping. Proposals for future funding ...
Date: May 14, 1999
Creator: Hassan, T. & Matzen, V.C.

Assessing Cumulative Thermal Stress in Fish During Chronic Exposure to High Temperature

Description: As environmental laws become increasingly protective, and with possible future changes in global climate, thermal effects on aquatic resources are likely to receive increasing attention. Lethal temperatures for a variety of species have been determined for situations where temperatures rise rapidly resulting in lethal effects. However, less is known about the effects of chronic exposure to high (but not immediately lethal) temperatures and even less about stress accumulation during periods of fluctuating temperatures. In this paper we present a modeling framework for assessing cumulative thermal stress in fish. The model assumes that stress accumulation occurs above a threshold temperature at a rate depending on the degree to which the threshold is exceeded. The model also includes stress recovery (or alleviation) when temperatures drop below the threshold temperature as in systems with large daily variation. In addition to non-specific physiological stress, the model also simulates thermal effects on growth.
Date: November 14, 1999
Creator: Bevelhimer, M.S. & Bennett, W.R.

ASTM Standards for Reactor Dosimetry and Pressure Vessel Surveillance

Description: The ASTM standards provide guidance and instruction on how to field and interpret reactor dosimetry. They provide a roadmap towards understanding the current ''state-of-the-art'' in reactor dosimetry, as reflected by the technical community. The consensus basis to the ASTM standards assures the user of an unbiased presentation of technical procedures and interpretations of the measurements. Some insight into the types of standards and the way in which they are organized can assist one in using them in an expeditious manner. Two example are presented to help orient new users to the breadth and interrelationship between the ASTM nuclear metrology standards. One example involves the testing of a new ''widget'' to verify the radiation hardness. The second example involves quantifying the radiation damage at a pressure vessel critical weld location through surveillance dosimetry and calculation.
Date: September 14, 1999
Creator: GRIFFIN, PATRICK J.

Atomic-Scale Engineering of the SiC-SiO{sub 2} Interface

Description: We report results from three distinct but related thrusts that aim to elucidate the atomic-scale structure and properties of the Sic-SiO{sub 2} interface. (a) First-principles theoretical calculations probe the global bonding arrangements and the local processes during oxidation; (b) Z-contrast atomic-resolution transmission electron microscopy and electron-energy-loss spectroscopy provide images and interface spectra, and (c) nuclear techniques and electrical measurements are used to profile N at the interface and determine interface trap densities.
Date: November 14, 1999
Creator: Buczko, R.; Chung, G.; Di Ventra, M.; Duscher, G.; Feldman, L.C.; Huang, M.B. et al.